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[music throughout] In the scorching upper

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reaches of the Sun’s atmosphere, the corona, scientists have just seen a new type of magnetic

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explosion. The explosion known as forced or

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controlled magnetic reconnection, is triggered by an eruption on the Sun which causes

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tangled magnetic field lines to explosively snap and realign, shooting

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out particles and energy. The discovery may help

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scientists understand a key mystery about how the corona, the Sun’s outermost layer,

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is millions of degrees hotter than layers below it.

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Previously, scientists had only seen spontaneous reconnection.

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which is not necessarily linked to an eruption or external forcing on the Sun.

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The forced reconnection event was clearly visible

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when the scientists used observations from NASA’s Solar Dynamics Observatory

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to look at a wavelength of showing plasma heated to six million degrees.

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The data showed a prominence,

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a large loop of plasma moving up from the visible surface of the Sun, the photosphere

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In a series of images take over an hour, the

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prominence could be seen falling back into the photosphere.

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En route, the prominence ran into a snarl of magnetic field lines, causing them to

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reconnection in a distinct X shape. The data from the event

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showed that the prominence, which was fairly cool relative to the blistering corona,

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gained heat from the event. The temperature of the reconnection point was also

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elevated. This suggests that forced reconnection might be

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one way that the corona is heated locally.

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The scientists are continuing to look for more forced reconnection events.

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With more observations, they can begin to understand the mechanics behind the

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reconnection and how often it might happen.

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[music fades]

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silence